Toe-to-hand transfers face various intra-operative and post-operative complications requiring immediate salvage interventions. We present a case of vascularized toe joint transfer complicated by severe vasospasm during papaverine shortage, successfully salvaged using retrograde anastomosis. This experience, combined with literature review, provides a comprehensive framework for managing failing toe transfers including vasospasm, poor donor vessel pressure, arterial thrombosis, and tissue necrosis. Understanding these salvage techniques is essential for any surgeon considering toe-to-hand reconstruction, as prompt recognition and intervention can convert potential failures into successful outcomes.

An animal's ability to taste is critical for nutrient selection and rejection of potentially toxic substances. Factors such as age, diet, environment, and internal state can also influence food-related behavioral outcomes. One such factor-exposure to taste cues during early development-remains poorly understood. Here, we evaluate how larval taste input affects adult feeding preference in Drosophila melanogaster. We find that larval dietary exposure to papaverine, a bitter alkaloid, attenuates feeding avoidance of papaverine in adult flies. This behavioral modification appears compound specific, occurring with papaverine but not with other bitter chemicals tested, and selective, with feeding preferences for other bitter tastants unaffected. We identify contributions of larval bitter taste function, taste projection populations, and the cyclic AMP (cAMP)-phosphodiesterase dunce in supporting this behavioral modification. Together, our findings suggest that developmental experiences with bitter compounds can change taste-mediated behaviors through defined sensory and neural circuit components.

Psoriasis is a chronic, immune-mediated inflammatory skin disease affecting at least 2% of the global population. Papaverine, an alkaloid with known anti-inflammatory, anti-cancer, and RAGE-antagonistic properties, has not been previously evaluated for anti-psoriatic activity. This study investigated the protective effects and mechanisms of papaverine in an imiquimod (IMQ)-induced psoriasis-like model in BALB/c mice. Papaverine treatment significantly ameliorated clinical symptoms, as evidenced by reductions in psoriatic lesions, skin thickness, severity index scores, T- and B-cell infiltration, and cutaneous angiogenesis. It also downregulated IMQ-induced mRNA expression of keratinocyte differentiation markers Krt10 and Ivl. Flow cytometric analysis revealed a marked reduction in B220[+]CD138[+] plasmablasts and B220[-]CD138[+] plasma cells in both circulation and spleen. These effects were associated with modulation of key transcription factors involved in plasma cell differentiation, including Prdm1, Xbp1, and Bcl6. Notably, the population of CD3[+]CD4[-]CD8[-] double-negative T cells was also decreased following papaverine administration. Inflammatory cytokine and chemokine mRNA levels in IMQ-exposed skin-namely Il1b, Il6, Ifng, Mcp1, Il22, S100a7, and Ager-were significantly suppressed. These findings suggest that papaverine ameliorates psoriasis-like symptoms through inhibition of proinflammatory cytokines and suppression of aberrant plasma cell differentiation. In conclusion, papaverine demonstrates therapeutic potential as a candidate for the treatment of psoriasis.

Non-occlusive mesenteric ischemia (NOMI) is a life-threatening form of acute mesenteric ischemia (AMI), caused by severe intestinal hypoperfusion in the absence of an obstructive lesion of the mesenteric arteries. Early diagnosis and management remain challenging because the condition often develops in critically ill patients and frequently presents with non-specific clinical manifestations. This comprehensive narrative review summarizes the current evidence regarding the management of NOMI. A comprehensive literature search was performed. Evidence relating to hemodynamic resuscitation, imaging, catheter-directed therapies, surgical management, bowel viability assessment, nutritional support, and postoperative care was critically synthesized. Current evidence supports immediate correction of the underlying low-flow state, optimization of systemic perfusion, and urgent multiphase computed tomography angiography as the cornerstones of management. Catheter-directed intra-arterial vasodilator therapy with papaverine may improve mesenteric perfusion in carefully selected patients without established bowel infarction, although supporting evidence remains predominantly observational. Conversely, patients with peritonitis, perforation, or convincing evidence of transmural necrosis require prompt surgical exploration, using damage-control principles when appropriate. Despite recent advances in critical care, imaging, and endovascular techniques, the available evidence remains limited by small retrospective studies and considerable heterogeneity. Early recognition, multidisciplinary management, and standardized institutional treatment pathways are likely to represent the most effective strategies for improving outcomes, while prospective multicenter studies are needed to establish evidence-based management algorithms and optimize patient selection for emerging therapeutic interventions.

Fixed dilated pupils at the end of neurosurgical procedures are typically considered an ominous sign, often indicating acute brain injury, brainstem compression, or herniation, and are associated with poor neurological outcomes. However, pharmacological causes must also be considered. Papaverine hydrochloride, a vasodilator commonly used during intracranial surgery for the management of cerebral vasospasm, has been rarely reported to cause transient pupillary dilation and fixation. We describe the case of a 48-year-old woman with hemifacial spasm who underwent retrosigmoid craniotomy and microvascular decompression of the left facial nerve. The intraoperative course was uneventful under total intravenous anesthesia. Papaverine (200 mg) was locally infiltrated to relieve vasospasm of the anterior inferior cerebellar artery. At the conclusion of surgery, bilateral fixed dilated pupils (7 mm, nonreactive) were observed, raising concern for catastrophic intracranial pathology. Urgent neuroimaging was planned. However, within 15 minutes, the patient developed spontaneous respiratory effort, responded to commands, and her pupils returned to normal size and reactivity. She was extubated uneventfully and subsequently made a complete recovery, being discharged home on postoperative day 6. This case highlights a rare but important confounding effect of papaverine infiltration during neurosurgery. Papaverine may induce transient mydriasis mimicking signs of devastating neurological injury. Awareness of this phenomenon is critical for anesthesiologists, neurosurgeons, and critical care teams to avoid unnecessary interventions and guide appropriate postoperative decision-making.

With the goal to develop coralyne-based ligands for abasic site-containing DNA (AP-DNA), different synthetic routes towards the functionalization of coralyne were tested. In particular, the alkylation of the benzylic position in papaverine and subsequent cyclization by treatment with acetic anhydride in sulfuric acid led to the synthesis of a coralyne derivative with an alkoxyamine-functionalized linker attached at position C13. Firstly, it was demonstrated with a resembling model compound that the alkylation of the coralyne scaffold does not influence the DNA-binding properties. Furthermore, it was shown that the alkoxyamine function can be readily released from a Boc-protected precursor and that the corresponding coralyne-alkoxyamine conjugate can operate as a ligand for AP-DNA and as inhibitor of enzymatic repair of abasic sites.

Papaverine (PPV) has long been used in obstetric practice to facilitate cervical dilatation, yet its mechanism of action remains poorly understood. This creates an apparent paradox, as experimental studies indicate that PPV suppresses several inflammatory signaling pathways traditionally considered essential for physiological cervical ripening, despite its reported clinical benefits during labor. In this narrative review, we critically integrate current knowledge of cervical ripening biology with the pharmacological actions of PPV to reconcile this discrepancy. We propose that the reported clinical effects of PPV may be explained predominantly by modulation of cervical biomechanics rather than by direct enhancement of inflammatory remodeling. In particular, smooth muscle relaxation and cyclic nucleotide-dependent signaling may reduce functional cervical resistance and facilitate cervical dilatation despite the predominantly anti-inflammatory molecular profile of PPV. Although this mechanistic framework remains hypothetical, it provides a biologically plausible explanation for the apparent discrepancy between the molecular and clinical effects of papaverine and highlights priorities for future experimental and clinical research.